Which point would map onto itself after a reflection across the line y= -x
a) -4,-4
b) -4,0
c) 0,-4
d) 4,-4

d

Step-by-step explanation:

D.  (4, -4).

Step-by-step explanation:

y = -x is a line that has a negative slope of  -1 ( rising to the left)  and passing through the origin. It makes an angle of 45 degrees with the x-axis.

So, for example the point ( 0,1 )will map onto( -1 , 0).

Any point which maps on to itself across this line will have to lie on the line.

If x = 4 y = -x = -4.

y = 3x+4

step-by-step explanation:

to find the slope

slope = (y2-y1)/ (x2-x1)

    = (-8-4)/ (-4-0)

    = -12/-4

  = 3

using the slope intercept form of a line

y= mx+b

we know the slope is 3

we know the y intercept is 4 ( the point where it crosses the y axis or x=0)

y = 3x+4

$54.99

step-by-step explanation:

$54.99 includes 500 min. if she does not exceed 500 min then her bill is $54.99